Maybe you are lucky and your cpu instructon set has a fast maximum_of_2_integers instruction, but more likely you wont be so lucky, in that case a simple bitwise OR might be worth a thought.
Note: max(a,b) ≤ a|b < 2 * max(a,b)
This approximation is surprissingly more usefull then it seems at first
2005-11-23
Fast approximate max of 2 integers
Fast greatest common divisor
How do we find the greatest common divisor of 2 integers? Try all integers which are ≤ then the arguments and select the largest which divides both with no remainder, works but its too slow. Or maybe factorize both, take the common factors and multiply them together like they probably told you in school, but thats still far too slow for anything but the small numbers in school excercies
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